i am a kenya citizen i am able to join qatar army...

You can apply for army recruitment at the Ministry of the Interior. Residents and non-residents can join in Qatar through the Ministry's electronic recruitment system.
But there are some conditions that must be met to complete the process of registration and admission of the application. These conditions are:
The applicant must be between age of 18 and 28 years.
The length of the applicant (Person) should be between 165 cm and 220 cm
The applicant should weigh between 50 kg and 90 kg
The applicant must have a secondary certificate or equivalent.
If you meet these conditions with, you can register for the recruitment in the Qatari army, use the link attached below, all you have to do is click on the link, the required page will open directly. Fill out the required data and attach the required attachments.
As for the police, only Qatari nationals are allowed to join the Police College, but I will attach to you the Qatar Police College link to review all the conditions of registration.